Chemistry and Stoichiometry Study Guide

A reaction should produce 10.0 g of product, but only 8.5 g is actually made. Percent yield =

• 85%

• 115%

• 80%

• 10%

A student calculates a theoretical yield of 25 g but recovers 22 g in the experiment.

• 110%

• 88%

• 25%

• 50%

If the actual yield is 14 g and the percent yield is 70%, what is the theoretical yield?

• 20 g

• 10 g

• 7 g

• 1 g

A student’s percent yield is 100%. This means:

• They lost product

• They produced more product than expected

• They produced exactly the expected amount

• The reaction failed

A reaction has a theoretical yield of 50 g, but the student obtained 40 g. Percent yield =

• 125%

• 90%

• 80%

• 60%

A reaction has an actual yield of 13 g and a percent yield of 65%. Theoretical yield =

• 8.45 g

• 20 g

• 65 g

• 5 g

How many moles are in 36 grams of H₂O? (Molar mass H₂O = 18 g/mol)

• 1 mol

• 2 mol

• 18 mol

• 0.5 mol

How many grams is 3 moles of CO₂? (Molar mass CO₂ = 44 g/mol)

• 14.7 g

• 88 g

• 132 g

• 3 g

How many molecules are in 2 moles of a substance?

• 6.02 × 10²³

• 2 ÷ 6.02 × 10²³

• 12.04 × 10²³

• 1.00 × 10¹²

Convert 4.5 × 10²⁴ molecules of NaCl to moles. (Use 6.02 × 10²³ particles = 1 mol)

• 7.48 mol

• 0.13 mol

• 2.25 mol

• 0.75 mol